Learn about the different TV display formats. HDTVs are wider than standard-definition TVs (SDTV). HDTV screens are 78 percent wider than they are tall. As a result, if your television is an HD TV, standard definition content will not properly fit your entire television screen, and will instead be stretched or alternatively display black bars on either side of the image to compensate. Below you will find a list of the different formats that your Digital Box can be set to display. The availability of these formats is dependent on what equipment you are currently using (Digital Box, Television).
HDTVs have an aspect ratio of 16:9 (16x9, 1.78:1, or widescreen), They are 78 percent wider than tall. This allows a much wider viewing area to be displayed on the screen and more closely mimics how your eyes actually see the world.
Letterbox is where film is displayed at its full width (even on a 16:9 HDTV or a 4:3 SDTV) and has black horizontal bars at the top and bottom of the screen. This process ensures no part of the film’s image is lost when viewed on any type of television.
Sides of the original widescreen image are often cropped off and the focus rests on the centre portion of the frame of the scene. Important visual information towards the sides of the picture can be lost.